With the inclusion of Alice (Isabel Lucas) in Transformers: Revenge of the Fallen, Michael Bay's movies redeemed the franchise's weirdest toyline: the Pretenders. While the movie was not particularly well received and won the Razzie for Worst Picture, Alice's inclusion was a great moment for fans of the series and viewers alike. The result was that it brought a level of modernity to that line of the robots in disguise.
Introduced in 1988 as part of the "G1" line in Marvel Comics UK, and adapted into the IDW and Super-God Masterforce continuities in subsequent years, the Pretenders focused on Transformers that could cover themselves in synthetic organic shells to hide the robot. Thus, they commonly took the form of human beings and would live like regular citizens until they had to attack. The shells on the tie-in action figures were removed from the front and back to reveal the robot within. Unfortunately, this line of Transformers was also met with confusion by many fans who didn't understand the purpose they fulfilled, and so wouldn't hide the real robotic characters within properly. Additionally, the subsequent waves of the Pretenders came with several quality issues, and were quickly written off. Ultimately, it was one of the Transformers' weirdest and least successful subtoylines, but Michael Bay's Transformers movie somewhat redeems it.
In Transformers: Revenge of the Fallen, Alice plays a Pretender Decepticon who infiltrates the college attended by Sam Witwicky (Shia LaBeouf). Like her comic/action figure counterpart, her robot self is also disguised by a synthetic organic tissue. However, the movie elevates the concept of the Pretenders and redeems their tarnished reputation among fans by giving the Pretenders a defined story purpose, and a reason for being. It also makes the transformation of the Pretenders conceptually a lot cooler by getting rid of the clunky execution of a removable shell. In Michael Bay's sequel, Alice's disguise is unnoticed by the entire college, until she reveals the robotic endoskeleton within, but she's also able to easily transform back into a human to remain disguised.
Another issue that the movie fixed was that the construction of the Pretenders action figures often limited the mobility of the Transformers within. When removed, there wasn't much the actual robot encased could do on its own, making the disguise seem more pointless. It also led to scale discrepancies, especially when characters like Bumblebee and Grimlock were added to later Pretender lines as they were far larger than human beings, thereby undermining the entire point of the Pretenders being able to pass as human. The shells themselves also varied in nature. With the Transformers Beast Wars Pretenders, the shells being in the form of animals on Earth addressed the unrealistic size problems, but the figures themselves provided no articulation or even weapons. In Transformers: Revenge of the Fallen, however, Alice is properly scaled, practical, and had self-contained weapons, giving her a full range of capabilities. The animal-like qualities in some of her movements was also a nice nod to the Beast Wars line.
While there is still overall some skepticism over the Pretenders and Transformers: Revenge of the Fallen as a movie, advances in figure technology and renewed interest in the line may still lead to a resurgence in their shelf lives. Many attempts since to bring back the Pretenders have been made, including the "Power of the Primes" line some years ago. Michael Bay's Transformers movies are often criticized for making decisions many audiences didn't enjoy. Still, it's undeniable that they led to a resurgence of popularity for the franchise that continues to grow. Hopefully, that continues with the spinoff movies on the horizon, such as the upcoming Transformers: Rise of the Beasts.